The study will enroll 344 patients with moderate to severe plaque psoriasis, who will be randomized into 2 groups (1:1 ratio): patients from the first group will receive BCD-057 subcutaneously (SC) at a dose 80 mg on week 0, then at a dose 40 mg on weeks 1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21 and 23. Then participants of this group will be invited for randomization at week 25 (in order to keep the double-blind design of the study), but it will have a formal character (assignment of a new randomization number and lot). Patients will continue to receive 40 mg of BCD-057 on weeks 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49 and 51.